Justinian II (Greek: Ἰουστινιανός Β΄, Latin: Iustinianus Augustus), surnamed the Rhinotmetos or Rhinotmetus (ὁ Ῥινότμητος, "the slit-nosed"), was the last Byzantine Emperor of the Heraclian Dynasty, reigning from 685 to 695 and again from 705 to 711. Justinian II was an ambitious and passionate ruler who was keen to restore the Empire to its former glories, but he responded poorly to any opposition to his will and lacked the finesse of his father, Constantine IV. Consequently, he generated enormous opposition to his reign, resulting in his deposition in 695 in a popular uprising, and he only returned to the throne in 705 with the help of a Bulgar and Slav army. His second reign was even more despotic than the first, and it too saw his eventual overthrow in 711, abandoned by his army who turned on him before killing him.

In 706, Justinian II elevated his infant son Tiberius as co-emperor. Following the overthrow of his father in December 711, Tiberius was murdered by the patrikios Mauros and John Strouthos, and buried in the Church of the Holy Unmercenaries.